1. Field of the Invention
This invention relates generally to a spark-ignition internal combustion engine, and more particularly to an apparatus for and a method of controlling a spark-ignition internal combustion engine of the type in which fuel is injected directly into a cylinder.
2. Related Art
There is known a conventional system (Japanese Patent Unexamined Publication No. 2-153257) in which fuel is injected directly into a cylinder by use of the air pressure. A conventional diesel engine utilizes a stratified combustion, and therefore the maximum output or power is low although the fuel consumption under a partial load is enhanced. On the other hand, a conventional gasoline engine has a drawback that although the maximum output or power is high because of a premixture combustion, the fuel consumption under a partial load is worsened because of a pumping loss.